Selective abortion, also known as selective reduction, refers to choosing to abort a fetus, typically in a multi-fetal pregnancy, to decrease the health risks to the mother in carrying and giving birth to more than one or two babies, and to also decrease the risk of complications to the remaining fetus(es). The term also includes performing the procedure when a fetus is likely to be born with a birth defect or impairment.


A woman may decide to abort for personal health reasons, for example, when she is at higher risk for complications because of diabetes.  Another example, although rare was reported in 2004 when an embryo became embedded in a cesarean section scar. In this care, selective abortion was successful at saving the mother and the remaining embryos.


More commonly, selective reduction is discussed in cases of multi-fetal pregnancy. In the general population, multi-fetal pregnancy happens in only about 1-2% of pregnant women.  But multi-fetal pregnancies occur far more often with women using fertility drugs.


Because women or couples who use fertility drugs have made an extra effort to become pregnant, it is possible that the individuals may be unwilling or uncomfortable with the decision to abort a fetus in cases of multi-fetal pregnancy.  Individuals engaging in fertility treatment will be made aware of the risks of multi-fetal pregnancy and of the medical options, including a reduction.



Selective reduction is usually performed between nine and 12 weeks of pregnancy and is most successful when performed in early pregnancy.  It is a simple procedure and can be performed on an outpatient basis. A needle is inserted into the woman’s stomach or through the vagina and potassium chloride is injected into the fetus.


Individuals who have chosen selective reduction to safeguard the remaining fetuses will be counseled prior to the procedure.  The counseling will include information regarding the relative risks to fetuses and the mother having the procedure as compared to not having the procedure.

Individuals seeking an abortion for any reason should consider the ethical implications whether it be because the fetus is not the preferred sex or because the fetus would be born with a severe birth defect.



Counseling should continue after the abortion because it is a traumatic event. Individuals may feel guilty about choosing one fetus over another. Mental health professionals should be consulted throughout the process.



About 75% of women who undergo selective reduction will go into premature labor. About 4-5% of women undergoing selective reduction also miscarry one or more of the remaining fetuses. The risks associated with multi-fetal pregnancy are considered higher.


Normal results

In cases where a multi-fetal pregnancy of three or more fetuses is reduced to two fetuses, the remaining twin fetuses typically develop as they would if they had been conceived as twins.